Management Team


Greg Mullen
Chief Executive Officer

Greg Mullen is the Chief Executive Officer of Theragnostics Limited and President of Theragnostics Inc. Greg is a founding member of Theragnostics since its formation in 2015.

Greg graduated with a PhD in Chemistry from the University of Kent and went on to Oxford University where he completed his post-doctoral research. Greg has a career spanning over 20-years in translational medicine. He has extensive product and clinical development experience across a range of small molecule and biological products. He has taken vaccines from discovery through to pediatric Phase 2b clinical trials while at the National Institutes of Health in the United States. In 2007, Greg joined the Department of Imaging Chemistry and Biology at King’s College London and his research group developed several imaging diagnostics for precision medicine in autoimmunity, heart disease and oncology. It was during this time that he co-invented the novel Ga-68 radiopharmaceutical chelator which enabled the development of cold PET kits. In 2012 Greg joined Oxford Immunotec as Research and Development Director where he was responsible for expanding their diagnostic product pipeline in chronic infections and autoimmunity. Greg went on to become Chief Scientific Officer at Mediso Ltd where he developed cancer specific imaging procedures to achieve high quality and accurate data to enable better diagnosis of cancer.

At Theragnostics, Greg has been instrumental in raising capital via grant funding and private investment. Greg is leading a team to expand their product portfolio and the commercialization of Ga-68 THP-PSMA, a prostate cancer imaging diagnostic.


Gareth Smith
Chief Operating Officer

Gareth Smith is the Chief Operating Officer of Theragnostics, joining the company in December 2016. Gareth completed a PhD in Chemistry at King’s College London with a focus on the development of strategies for labelling peptides and proteins in a single-step with fluorine-18. His career began in R&D at GE Healthcare where he worked on programs in neurology and oncology. During his time with GE his role evolved towards IP evaluation including commercial and technical evaluation of technologies for in-licensing.

Following 5 years with GE Gareth moved into technology transfer with the University of Oxford, where he was responsible for the protection and commercialisation of research arising from a wide-range of subjects. His work included in/out-licensing, contract negotiations and support for patent prosecution. In addition, he built business cases and teams for spin-out companies and helped raise capital for their formation.

At Theragnostics, Gareth is focused on the development of the product pipeline developing the THP-platform and licensing IP to strengthen the company. He is also responsible for the company’s broader business development activities.


George Skouteris
Chief Medical Officer

George is qualified in medicine, in GMC’s (UK) specialist’s register and has a Doctor of Philosophy in Biochemistry & Molecular Biology from the University of Oxford. He served in various positions within academia such as Group Leader in the Department of Pathology, Duke University Medical Center, USA, as Senior Investigator at the German Cancer Research Centre (DKFZ, Heidelberg) and Senior Lecturer at University College London, UK.

Since 2003 George has held various R&D and medical director positions within the Pharmaceutical industry, which include Eli Lilly (Oncology), Roche Products Ltd. (Oncology & Hepatitis), Daiichi Sankyo Inc. (Neuropathic Pain) and GSK (Immunology & Oncology).


George co-authored over 40 peer-reviewed publications, edited 3 books, and is co-inventor on 3 patents, mostly in the signal transduction and receptor-ligand interactions arena.


William Hartley
General Manager, US Operations

William (Bill) Hartley joined the company in June 2017 as Director of Quality and is now Interim General Manager of US Operations in support of global business strategies for Theragnostics. His responsibilities include management of Theragnostics’ US office, all aspects of quality activities related to the establishment and maintenance of quality systems, and management of third party manufacturers and distributors. Bill has 30+ years of experience in global GXP Quality Systems primarily in radiopharmaceuticals and with additional knowledge in the areas of Oral Solid, Biopharmaceutical and Medical Device manufacturing.

Bill received his business degree from Boston University and serves on the Board of Directors for the non-profit, Hope Builders Inc, which was formed in 2017 to aid in the rebuilding of homes on the island of Vieques, Puerto Rico, after Hurricane Maria devastated the island.


Baden Gowrie-Smith
Finance Director

Baden is a co-founding Director of Theragnostics, and brings to the company his experience in developing and financing SMEs. Baden co-founded and remains a Director of the UK’s largest biomethane transport infrastructure company, CNG Fuels, which was founded in 2014. He has experience developing businesses in energy distribution, mining and investment management. His previous career in investment management included six years with UBS in multi-asset class advisory as well as working in emerging markets private equity. Baden holds an MBA from London Business School, and both a Masters degree in Commerce and Bachelors degree in Economics from the University of Sydney.



Management Team


Greg Mullen

Chief Executive Officer

Greg Mullen is the Chief Executive Officer of Theragnostics Limited and President of Theragnostics Inc. Greg is a founding member of Theragnostics since its formation in 2015.

Greg graduated with a PhD in Chemistry from the University of Kent and went on to Oxford University where he completed his post-doctoral research. Greg has a career spanning over 20-years in translational medicine. He has extensive product and clinical development experience across a range of small molecule and biological products. He has taken vaccines from discovery through to pediatric Phase 2b clinical trials while at the National Institutes of Health in the United States. In 2007, Greg joined the Department of Imaging Chemistry and Biology at King’s College London and his research group developed several imaging diagnostics for precision medicine in autoimmunity, heart disease and oncology. It was during this time that he co-invented the novel Ga-68 radiopharmaceutical chelator which enabled the development of cold PET kits. In 2012 Greg joined Oxford Immunotec as Research and Development Director where he was responsible for expanding their diagnostic product pipeline in chronic infections and autoimmunity. Greg went on to become Chief Scientific Officer at Mediso Ltd where he developed cancer specific imaging procedures to achieve high quality and accurate data to enable better diagnosis of cancer.


At Theragnostics, Greg has been instrumental in raising capital via grant funding and private investment. Greg is leading a team to expand their product portfolio and the commercialization of Ga-68 THP-PSMA, a prostate cancer imaging diagnostic.


Gareth Smith

Chief Operating Officer

Gareth Smith is the Chief Operating Officer of Theragnostics, joining the company in December 2016. Gareth completed a PhD in Chemistry at King’s College London with a focus on the development of strategies for labelling peptides and proteins in a single-step with fluorine-18. His career began in R&D at GE Healthcare where he worked on programs in neurology and oncology. During his time with GE his role evolved towards IP evaluation including commercial and technical evaluation of technologies for in-licensing.

Following 5 years with GE Gareth moved into technology transfer with the University of Oxford, where he was responsible for the protection and commercialisation of research arising from a wide-range of subjects. His work included in/out-licensing, contract negotiations and support for patent prosecution. In addition, he built business cases and teams for spin-out companies and helped raise capital for their formation.

At Theragnostics, Gareth is focused on the development of the product pipeline developing the THP-platform and licensing IP to strengthen the company. He is also responsible for the company’s broader business development activities.


George Skouteris

Chief Medical Officer

George is qualified in medicine, in GMC’s (UK) specialist’s register and has a Doctor of Philosophy in Biochemistry & Molecular Biology from the University of Oxford. He served in various positions within academia such as Group Leader in the Department of Pathology, Duke University Medical Center, USA, as Senior Investigator at the German Cancer Research Centre (DKFZ, Heidelberg) and Senior Lecturer at University College London, UK.

Since 2003 George has held various R&D and medical director positions within the Pharmaceutical industry, which include Eli Lilly (Oncology), Roche Products Ltd. (Oncology & Hepatitis), Daiichi Sankyo Inc. (Neuropathic Pain) and GSK (Immunology & Oncology).


George co-authored over 40 peer-reviewed publications, edited 3 books, and is co-inventor on 3 patents, mostly in the signal transduction and receptor-ligand interactions arena.


William Hartley

General Manager, US Operations

William (Bill) Hartley joined the company in June 2017 as Director of Quality and is now Interim General Manager of US Operations in support of global business strategies for Theragnostics. His responsibilities include management of Theragnostics’ US office, all aspects of quality activities related to the establishment and maintenance of quality systems, and management of third party manufacturers and distributors. Bill has 30+ years of experience in global GXP Quality Systems primarily in radiopharmaceuticals and with additional knowledge in the areas of Oral Solid, Biopharmaceutical and Medical Device manufacturing.

Bill received his business degree from Boston University and serves on the Board of Directors for the non-profit, Hope Builders Inc, which was formed in 2017 to aid in the rebuilding of homes on the island of Vieques, Puerto Rico, after Hurricane Maria devastated the island.


Baden Gowrie-Smith

Finance Director

Baden is a co-founding Director of Theragnostics, and brings to the company his experience in developing and financing SMEs. Baden co-founded and remains a Director of the UK’s largest biomethane transport infrastructure company, CNG Fuels, which was founded in 2014. He has experience developing businesses in energy distribution, mining and investment management. His previous career in investment management included six years with UBS in multi-asset class advisory as well as working in emerging markets private equity. Baden holds an MBA from London Business School, and both a Masters degree in Commerce and Bachelors degree in Economics from the University of Sydney.